As winter sets in, the vines generally take a well earned rest after producing the grapes for the harvest in autumn. That is except for the vines that are used to produce ice wine, an exclusive style of wine that is only ever produced in small quantities and not necessarily every year.

Ice wine is made from frozen grapes that are still on the vine, and to be in accordance with the International Organisation of Vine and Wine’s regulations, the temperature has to have reached at least -7°C. What an idea to make wine from frozen grapes! It’s apparently in Austria that the first wine was made in this way, and as with many great discoveries, it was completely by accident. At the end of the 18th century in a year when the first winter frosts came very early, the harvesters picked some grapes that had already frozen, but the resulting wine was excellent, contrary to all expectations!

The slight problem is that in order to have frozen grapes, you need the cold! And as it doesn’t necessarily come every year, it’s quite a bet for the winemaker to take, deciding to leave the grapes on the vines in the hope that the temperature will drop sufficiently to make ice wine, eiswein or vin de glace, as it is also known in some regions.

Why do the grapes have to be left on the vine for such a long time? As for the vendanges tardives or late harvest wines, the grapes are left longer to give them the chance to obtain a much higher sugar level (the grapes used for the vendanges tardives also have the noble rot to help increase the concentration of sugar). The sugar levels are increased by the effects of the frost, and the grapes are picked and transported to the chai when they are still frozen. The grapes are then pressed whilst frozen, so some of the grape juice remains as ice crystals with the stalks, pips, and grape skins after pressing. This further increases the sugar levels of the extracted juice.

Freezing also gives the wine greater acidity, which counterbalances the sugar, giving sweet wines which are very aromatic and fresh on the palate.

But be warned. Not everyone or everywhere can produce ice wine. We’ve already mentioned that you need a minimum temperature, and across the Atlantic in the US and Canada, regulations for making ice wine stipulate at least -12°C. The freezing temperatures can in no way be produced artificially, and it is also against the charter to add sugar to the must. These conditions mean that the production of ice wine remains very restricted compared to classic wines.

The main ice wine producing regions are Austria, Germany and Alsace in Europe, and Canada and the United States in North America. The main grape varietals used to make ice wine are riesling, grüner vetliner and gewurztraminer for the white ice wines, and merlot, cabernet franc and cabernet sauvignon for red ice wines.

So how is ice wine best served? Unsurprisingly, cold! Between 4 and 8°C, it can be enjoyed as an aperitif or as a dessert wine, but is best tasted on its own to fully appreciate the harmony between the sugar and acidity. It pairs well with blue cheese or foie gras, and if you have the patience, is a wine that can be kept in the cellar for a few years!